<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>CSS练习</title>
    <style>
        .class01{
            border: 1px red solid;
            font-size: 30px;
            color: red;
        }
        .class02{
            color: blue;
            border: 3px dashed blue;
        }
    </style>
</head>
<body>
    <div class="class01">div标签1</div>
    <div class="class02">div标签2</div>
    <span class="class01">span标签1</span>
</body>
</html>